Hydroponic tank



FIG. 1 is a perspective view of the hydroponic tank showing my new design;

FIG. 2 is a top plan view of the hydroponic tank shown in FIG. 1;

FIG. 3 is a side elevation view of the hydroponic tank shown in FIG. 1; and

FIG. 4 is an end view of the hydroponic tank shown in FIG. 1. 

The ornamental design for a hydroponic tank, as shown. 